As is a black key, immediately next to A. It sounds at 415.3 Hz in octave 4.
As can also be written as Gis. These are enharmonic equivalents: the same pitch, the same key on the piano, a different name on the page. Which spelling is correct depends on the key and on how the note functions, not on the sound.
Frequencies for As in scientific pitch notation, with A4 tuned to 440 Hz.
| Note | MIDI | Frequency |
|---|---|---|
| As1 | 32 | 51.91 Hz |
| As2 | 44 | 103.83 Hz |
| As3 | 56 | 207.65 Hz |
| As4 | 68 | 415.3 Hz |
| As5 | 80 | 830.61 Hz |
| As6 | 92 | 1661.22 Hz |
| As7 | 104 | 3322.44 Hz |
The most common chords built with As as the root.
Keys and scales that use As as their tonic.
As is a black key, immediately next to A.
As4 sounds at 415.3 Hz with A4 tuned to 440 Hz.
As can also be written as Gis. They are the same pitch spelled differently.